Question: Fit based on Excel data

Hello

I am working on a project where I need to find the parameters of the formula:

1/2*a*erfc(1/2*2^(1/2)*(-x+m1)/s1)+(1/2-1/2*a)*erfc(1/2*2^(1/2)*(-x+m2)/s2)

which is the formula for the cumulative distribution for two gaussian peaks, one with average m1 and standard deviation s1, the other m2 and s2, with weights a and (1-a). I have data in excel that form the gaussian distribution but now I need to find the parameters of the formula that fits these data.

Is there a command in maple to find these parameters or how do I start? And do I need to upload the data from excel to maple or do I need to insert only some values?

Some one who could help me, because it is really hard and I find no information for this.

Hasselhof